Improvement in boilers



G. SELDEQN 8@ T. M. NAGLE.

BOILER.

TATEs .QNTTnn PATENT rn GEORGE SELDEN AND THEODORE M. NAGLE, OF ERIE, PENNSYLVANIA; SAID NAGLE ASSIGNOR TO SAID SELDEN.

IMPRovEMENT |N BolLERs.

Specification forming part of Letters Patent No. 186,762, dated January 30,1877; application filed February 28,1876.

To all lwhom it may concern:

Be it known that we, GEORGE SELDEN and Tnnononn M. NAGLE, both of the city and and county of Erie, State of Pennsylvania, have invented certain new and useful Improvements in Boilers, of which the following` is a full, clear, and exact description, reference being had to the accompanying drawings, making part of this specification, in which- Figure 1 represents a vertical section through an upright range or bath boiler, and Fig. 2 a horizontal section through the same. Fig. 3 represents a vertical section through an upright boiler, and Fig. 4 a horizontal section through the same.

Similar letters of reference denote corresponding parts wherever used.

Our invention relates more particularly to the manner of' combining the heads with the cylinder of the boiler, with a View to dispensing with the ordinary unreliable joints formed by riveting these parts together; and consists, rst, in uniting the anged heads with the cylinder, by shrinking them thereon, and,

. further, securing them in place, where necessary, by the aid of' one or more through-bolts; secondly, in combining the fire-pot cylinder in an upright boiler with the boiler-cylinder, by means of a double-flanged ring, with which the two cylinders are united, either by screwthreads or by shrinking, as hereinafter explained; thirdly, in combining the head of the fire-pot, or the disk intermediate between the lire-pot and the boiler, with the fire-pot cylinder, by means of a screw-thread cut upon the periphery of said head or disk, and a corresponding thread cnt upon the inner periphery of the upper end of the fire-pot cylinder; and, lastly, in certain details of construction hereinafter described.

In the accompanying drawings, A represents the boiler-cylinder, which, in the case of the range-boiler, where the diameter usually is not great, it is preferred to make of aseamless tube, rolled or otherwise formed in any usual or preferred way. It may be made with a lap-weld extending its whole length, or, in the larger boilers, it may have its edges joined by rivets, and calked in the usual way, except at the ends, where, for the purpose of uniting the heads, as hereinafter described, said edges are united by a lap-Weld.

The heads B may be made in the concaveconvex and flanged form shown in Fig. l, or they may be in the form of flanged disks, as shown at B', Fig. 3, and the flanged rim of' the head together with the periphery of the end of the cylinder being turned or otherwise made accurately to match each other, the heads, or rather the flange b thereof, is placed over and shrunk upon the end of the cylinder. For further securing the heads upon the cylinder, longitudinal through bolt or bolts c may be employed. With the heads thus ap? plied thejoint can be readily calked and made thoroughly tight, in the usual manner.

At the lower end-of the uprightsteam-boiler, Figs. 3 and 4, where it is necessary to partially inclose or surround the fire-pot, a ring, D, is employed, provided with the outer or peripherical [lange d, and the inner circular liange d upon its inner edge, as shown.

These flanges may be provided with screwthreads, the outer one, d, on its inner face, and the inner one, d', upon its outer face or periphery, and the boiler and lire-pot cylinders may be provided on their ends with corresponding screW-threads for uniting them to the ring Dor the flanges d d' may be turned or made true on the faces referred to, and the correspondingfaces` of' the cylinders being simi` larly turned, and made to match the flanges closely, the flange d may be shrunk upon the cnd of the boiler-cylinder, and the lower end of the fire-pot cylinder E, in turn, may be shrunk upon the ange d', and by calking, or otherwise, as may be necessary, a tight joint is formed in either case, between the boiler and tire-pot cylinders and the ring D.

Through-bolt c, before referred to. may be employed for further strengtheningjtheunion between the ring D and head B, and the boiler-cylinder or transverse bolts passing through both cylinders A and E, and the two flanges, d d', may be employed, if preferred.

The upper end of the fire-pot cylinder E has a screw-thread cut upon its inner face or periphery, and the head or end F, made'in disk form, has a corresponding screw-thread cut upon its edge or periphery, and is screwed of pressure of the contents of the boiler. Thus the pressure upon the cylinder A is outward, and its ends are therefore surrounded and strengthened by the angesl bd, Ste., while thev pressure upon the fire-pot cylinder being inward, said cylinder is made to surround the sustaining-head F and flange d', thereby causing the pressure to tend rather to tighten than to open the jointsan importantfeature ill the construction of boilers, as herein described.

The disk form of the head obviates the difficulty experienced in the use of the two thicknesses of metal, as usually employed, and riveted together, viz the rapid burning out of the inner thickness which is exposed to the re, and is unprotected by the water. A ange on the periphery ofthe disk may, however be employed, if desired, for giving a greater extent of holding screw-thread, but this, by preference, will be made upon the upper face of the disk, where it will be protected by the water. The central part of the head F may be dished, or made in the form of a firedome, if desired. Tubes or dues ff connect the heads B and F, serving to increase the heating-surface While they carry off the products of combustion. These tubes are joined to the heads in any usual manner, and the pressure upon the heads being in opposite directions, the tubes serve to stiften them, 'and to strengthen their connection with the cylin- In some casesit may be found desirable to submerge the upper ends of the tubes ff, for

protecting them from injury from the heat. This is done by employing a cylinder and doubleanged ring, similar to E and D, in` verted, and applied to the upper end of the boiler, thereby bringing the upper endspof the tubes f below the water-line in the boiler.

In the construction of range-boilers, the metal employed is usually too thin to insure a durable joint with the pipes of cocks. This dculty is-obviated byinserting short headed' tubes g, (see Fig. 1,) provided with screwthreads, and held firmly in place by nuts h, which, in connection with the heads g', clamp and support the metal of the boiler between them, as shown, the tubes g themselves forming the points of attachments of the pipes or cocks with the boiler. The coal-chute and the grate may be applied in connection with the upright boiler and the inclosed fire-pot E, in any usual or preferred manner.

Having now described our invention, what `we claim as new, and desire to secure by Let- GEO. SELDEN.v THEODORE M. NAGLE. Witnesses:

U. L. CLEVELAND, E. P. SELDEN. 

